Liquefied Petroleum Gas (LPG), a gas mixture consisting primarily of propane (C3H8) and butane (C4H10) – both saturated, chain-type hydrocarbon compounds – normally occurs as liquid natural gas when crude oil is being pumped from significant depths, or is obtained as a by-product in the crude oil refining process. Propane is non-poisonous, colourless and odourless, and has a mild narcotic effect at high doses. Butane is also colourless and odourless, hardly soluble in water, but slightly soluble in alcohol and ether. In larger doses, butane has a narcotic effect similar to propane.

LPG is liquid at a low pressure level and can be stored and transported in suitable containers. The ignition temperature is around 450 ºC. LPG has a very high temperature expansion coefficient and therefore reacts to every temperature fluctuation with a corresponding change in volume. In certain countries this factor is not taken into account when unloading or dispensing LPG; in other words no appropriate, temperature-dependent correction factor is applied. This generally results in less than favourable terms for consumers.

Multivariable flow measurement
The above issue was recognised early on by Endress+Hauser who as a consequence developed the LPGmass – a new flow meter designed especially for unloading and dispensing LPG according to the Coriolis measuring principle. This meant that it was finally possible to fulfil the call from various consumer organisations for temperature compensation.

As a multivariable Coriolis flow meter, the LPGmass measures several process variables simultaneously: Mass flow, fluid density and fluid temperature. This means it is possible to display the measured full scale value in volumetric units as well using conversions internal to the device together with the temperature compensation or by taking the API table into account.

The LPGmass is the first flow meter ever to integrate the internationally recognised API table 53 (API = American Petroleum Institute) to take the temperature expansion coefficient into account. API is the largest lobbying association for the oil and gas industry in the USA, including the petrochemical industry. An important part of API’s work is creating technical guidelines and standards. The impact of the API extends far beyond the USA.

The LPGmass was developed primarily for two highly typical and frequently occurring applications:

• Refuelling vehicles via fuel dispensers
• Distributing LPG by truck to small consumers such as small and medium-sized companies.

Other applications for the LPGmass are also entirely feasible such as private residences and blocks of flats.

The large range of nominal diameters from DN 8 to DN 40 allows the customer to select the most suitable measurement device for their application and his flow rates:

• Refuelling vehicles → DN 8, DN 15, DN 25
• Unloading trucks → DN 25, DN 40

Unique features

• The LPGmass sets new standards because safety and reliability during operation are always given first priority when handling liquefied gas:
• High operational safety due to its perfect production quality
• Space-saving, exceptionally compact and robust design; the ideal replacement for piston dispensers
• Integrated temperature sensor as standard and API conversion table for volume correction for standard volume measurement
• High level of resistance to vibration, e.g. for operation on trucks
• No moving parts or seals
• Excellent measuring accuracy thanks to traceable, accredited calibration facilities
• World-wide accepted Ex-approvals
• Numerous custody transfer approvals for commercial transactions

Simple and safe commissioning
The “FieldCare” configuration and service software from Endress+Hauser is a simple, dependable way to commission measuring instruments and to modify device parameters. The “Fieldview” add-on module also allows you to visualise measuring data, to display the data in graphical form and evaluate the data for diagnostic purposes, right down to individual measuring points. This means that operators of LPG systems can gain insights into the dispensing process and can optimise this process or track down irregularities if required.

Define and order the right instrument online
Choosing and ordering the most suitable product for your application according to industry requirements is now possible in one online workflow with Endress+Hauser. The 24 hour online access to all relevant instrument data simplifies and streamlines the processes from engineering to operations.

The integrated selection and sizing tools in the Online Shop speed up your engineering and purchasing processes. Upon entering your process parameters you are offered a selection of suitable devices. The link to the product database ensures that you have all the up-to-date information, prices and production times to help you make the most appropriate decision.

Speed up supply chain
As soon as you release the order or request a quotation, the product configuration will be transferred to the local Endress+Hauser contact online. Ordering online facilitates prompt delivery. During maintenance you can easily identify spare parts and order them instantly 24 hours a day.

For further details contact Frans van den Berg of Endress+Hauser on TEL: 011 262 8000 or visit www.za.endress.com